Physico-chemical characterization of pine cone shell and its use as biosorbent and fuel.

Physico-chemical properties of pine cone shell have been determined. Results of characterization study showed that pine cone shell could be used as biosorbent of nickel from aqueous solutions in a fixed-bed column and later as input material in thermochemical processes. To study the behavior of Ni-loaded pine cone shell as fuel, non-isothermal thermogravimetric tests were performed. These tests showed that, in nitrogen atmosphere, the main decomposition occurs from 200°C to 500°C and, in oxidant atmosphere, the behavior is of type "combustion+pyrolysis" (at higher temperatures there is a clear decomposition of residue formed during the initial steps). Finally, the effect of the presence of Ni was analyzed. Thermogravimetric curves did not change their profile and the total amount of nickel was detected in char-ash fraction and not in flue gases. These results suggest that nickel does not form volatile compounds at considered operational conditions.